Flushing system

ABSTRACT

In a urinal flushing system, the supply of water through a supply pipe is controlled by a normally closed solenoid valve, the solenoid valve being energized by a timer circuit including a heat-sensitive element positioned at the inner surface of the bowl.

llnited States Patent Gross 1 Mar. 14, 1972 [54] FLUSHING SYSTEM [72] Inventor: William Keith Gross, Agincourt, Ontario,

Canada [73] Assignee: Canadian Seating Company Limited,

Toronto, Ontario, Canada 221 Filed: Dec.8,1969

211 Appl.No.: 883,135

[52] US. Cl ..4/l00 [51] Int. Cl ..E03d 13/00 [58] Field of Search ..4/l00, DIG. 3, 101, 249, 102,

[56] References Cited UNITED STATES PATENTS III 923 l ,44 I ,007 Littlefield ..4/100 1,740,860 12/ 1929 Hansen ..4/ 108 2,388,990 11/1945 Nelson et a1. ..4/101 3,010,119 11/1961 Franke ..4/249 3 ,090,967 5/1963 Erhardt ..4/67 3,115,643 12/1963 Whitney .4/100 3,416,162 12/1968 I-Iamblen ..4/1OO Primary Examiner-Samuel B. Rothberg Assistant Examiner-Henry K. Artis Attorney-Maybee & Legris [57] ABSTRACT In a urinal flushing system, the supply of water through a supply pipe is controlled by a normally closed solenoid valve, the solenoid valve being energized by a timer circuit including a heat-sensitive element positioned at the inner surface of the bowl.

2 Claims, 3 Drawing Figures He 1 S nsiiive Swnch POWER H PACK ' TIMER FLUSI'IING SYSTEM This invention relates to an automatic flushing system and is concerned particularly with automatic flushing systems for urinals and the like.

Such flushing systems have hitherto depended on timers which ensure flushing of the bowls at regular intervals, irrespective of requirements, or alternatively they have been remotely controlled by the opening and closing of doors. 1n the former case there is a considerable wastage of water in many instances, and in other instances the flushing requirements are not always met. Remote controlled, door-operated flushing systems are complicated and expensive.

It is an object of the present inventionto provide a urinal flushing system which is relatively simple and fully automatic, while meeting the flushing requirements. The system according to the invention is controlled by a solenoid valve which is energized in accordance with the operation of heat-sensitive switch, the valve remaining open for a predetermined time depending on the operation of an electric timer connected in circuit with the switch. The urinal bowl must not be of a heat conducting material, such as porcelain or cast-iron, but should be made of a nonconducting material such as a moulded fiberglass-reinforced plastic, or acrylic plastic. Preferably the bowl is fully recessed in the wall when installed.

One embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:

FIG. 1 is a sectional, diagrammatic view of a urinal and flushing system;

FIG. 2 is a schematic circuit diagram of the control circuits for the flushing system, and

FIG. 3 is a sectional view of one form of timer device.

Referring to FIG. 1, a urinal installation comprises a bowl 1 having a rim which provides a peripheral flange 2, defining a frontal opening which lies in a substantially vertical plane. The bowl 1 is fully recessed into a wall 3, against which the flange 2 is fitted. The bowl 1 is molded from a nonconducting (i.e., not heat-conducting) plastic material, and is fonned with a concave inner surface 4, a drain outlet being provided at its lower end and connected to a drain pipe 5. A stainless steel screen 6 covers the drain outlet. A conventional water inlet 7-, for spraying or supplying water over the inner surface 4 is positionednear the top of the bowl, a main water supply pipe 8 being connected to the inlet, and the supply of water through the pipe 8 being controlled by a solenoid valve 9. The solenoid valve is normally closed, and prevents the supply of water through the pipe 8, but is opened when its solenoid is energized as described below.

The solenoid valve 7 is energized from a power pack 10, supplied from the mains 11, in accordance with the condition of an electric timer 12. The timer 12 is operated in accordance with the operation of a heat-sensitive switch 13 having a bimetallic, heat-sensitive element positioned at the inner surface 4 below the screen 6. The heat-sensitive switch is operated automatically whenever the urinal is used, the switch contacts opening again whenever cold water from the inlet 7 falls on the heat-sensitive element. Despite the reopening of the switch contacts, the solenoid valve remains open for a time determined by the timer 12, as described below.

Referring now to FIG. 2, the solenoid valve 9 has an energizing circuit 14 connected to a first pair of terminals 15,16 of the timer 12, and the timer has a second pair of terminals 17,18 connected in circuit with the heat-sensitiveswitch 13 and the supply source 10. The switch 13 includes a pair of normally open switch contacts in circuit with the supply, which normally prevents energization of the timer. The switch contacts are closed and reopened in accordance with the temperature of the heat-sensitive element 19.

The timer 12 is shown in detail in FIG. 3. It comprises a cylindrical casing defining an internal cylindrical chamber, and the chamber is divided into first and second compartments, 21,22, by an axially movable piston 23 fitted with a piston ring 24. Attached to one side of the piston 23 is an axially extending magnetic armature 30 which moves along the axis of a solenoidal energizing coil 25. Attached to the other side of the piston is a projection 26 of electrically insulating material, which engages a spring blade 27 carrying one of a pair of switch contacts 28. Normally, the piston assembly is urged by a compression spring 29 in the direction to separate the contacts 28, but when the coil 25 is energized, the armature 30 is pulled into the coil, the piston assembly moving against the force of the spring 29 to permit the contacts 28 to close. The energizing circuit of the coil 28 is connected to the coil by terminals 17,18, terminal 17 being mounted on the metal casing 20, and the terminal 18 being insulated from the casing by an insulating bush 31. The ends of the coil 28 are, of course, connected respectively to the casing 20 and the terminal 18.

The switch contacts 28 are connected in the energizing circuit of the solenoid valve 9 by way of the terminal 15 mounted on the casing 20, and terminal 16 which is insulated from the casing by a bush 32.

A relatively wide passage 33 interconnecting the compartments 21,22, and a nonreturn flap valve 34 cooperating with the passage, permit the flow of fluid, in this case air, from compartment 22 to compartment 21, but not in the opposite direction. The return flow must be by way of a relatively narrow, bleed passage 35 interconnecting the compartments 21,22, the rate of fluid flow through the passage being adjustable by an adjustable needle valve 36.

In the operation of the system, the solenoid valve 9 is normally closed, preventing flushing; energized, contacts of the heat sensitive switch 13 are open, and the timer 12 is inoperative. When the temperature of the heat-sensitive element 19 of the switch 13 rises to a certain value, the switch contacts close, thus completing the energizing circuit 14 of the timer coil '25, and the latter is energized. The armature 30 is attracted, pulling the piston assembly to the right (as shown in FIG. 3), and the switch contacts 28 close, thus completing the energizing circuit of the solenoid valve 9. The latter opens, and cold water is supplied to the inlet 7 via the supply pipe 8, and directed over the inner surface 4 of the bowl. As soon as the cold water touches the heat-sensitive element 19, the heatsensitive switch 13 opens, and the timer coil 9 is deenergized. The contacts 28 are not opened immediately, however, because the air cannot return from compartment 21 to compartment 22, but must return via the restricted bleed passage 35. The return of the piston 23 to a position at which it will open the contacts 28 is thus delayed in accordance with the setting of the needle valve 26. Thus the solenoid valve 9 remains energized, to permit the flushing water to flow, for a time determined by the timer.

What I claim as my invention is:

1. In combination, a urinal bowl of nonconducting material, the bowl having a drain outlet and a water inlet disposed to supply water over the inner surface of the bowl, a water supply pipe connected to the water inlet, a normally closed solenoid valve for controlling the supply of water through the supply pipe, a first energizing circuit for the solenoid valve, timer means, said timer means providing a normally open switch connected in said first energizing circuit, electric means for closing the switch to energize the solenoid valve, and means for preventing reopening of the switch until a predetermined time has elapsed, and a second energizing circuit for the switch closing means, said second energizing circuit including a heat-sensitive switch having a heat-sensitive element positioned at said inner surface and being responsive to temperature to initiate operation of the timer means, and said timer means comprises a casing defining a cylindrical chamber, a piston axially movable in the chamber and defining first and second compartments thereof, a first passage connected between the first and second compartments, a nonreturn valve cooperating with the first passage to permit fluid flow in one direction only therethrough, a second, bleed passage connecting the first and second compartments, a pair of normally open switch contacts connected in said first energizing circuit, an energizing coil connected in said second energizing circuit,

second, bleed passage.

2. The combination of claim I, wherein the urinal bowl has a rim defining a frontal opening which lies in a substantially vertical plane and wherein the bowl is fully recessed in a wall, the water supply and drain connections, and the solenoid valve and circuit means, lying behind the wall.

R i ii i t 

1. In combination, a urinal bowl of nonconDucting material, the bowl having a drain outlet and a water inlet disposed to supply water over the inner surface of the bowl, a water supply pipe connected to the water inlet, a normally closed solenoid valve for controlling the supply of water through the supply pipe, a first energizing circuit for the solenoid valve, timer means, said timer means providing a normally open switch connected in said first energizing circuit, electric means for closing the switch to energize the solenoid valve, and means for preventing reopening of the switch until a predetermined time has elapsed, and a second energizing circuit for the switch closing means, said second energizing circuit including a heat-sensitive switch having a heat-sensitive element positioned at said inner surface and being responsive to temperature to initiate operation of the timer means, and said timer means comprises a casing defining a cylindrical chamber, a piston axially movable in the chamber and defining first and second compartments thereof, a first passage connected between the first and second compartments, a nonreturn valve cooperating with the first passage to permit fluid flow in one direction only therethrough, a second, bleed passage connecting the first and second compartments, a pair of normally open switch contacts connected in said first energizing circuit, an energizing coil connected in said second energizing circuit, means connected to the piston for maintaining the switch contacts normally open, an armature connected to the piston and operable by the energizing coil, when energized, to move the piston to permit closing of the contacts, and a spring for returning the piston to its initial position, the switch contacts remaining closed until the piston returns to its initial position and for a time determined by the rate of fluid flow through the second, bleed passage.
 2. The combination of claim 1, wherein the urinal bowl has a rim defining a frontal opening which lies in a substantially vertical plane and wherein the bowl is fully recessed in a wall, the water supply and drain connections, and the solenoid valve and circuit means, lying behind the wall. 